Process of tanning



7 heavy skins.

NITED STATES PATENT OFFICE.

GUSTAV RUEMELIN, OF MILWAUKEE, WISCONSIN.

PROCESS OF TANNING.

SPECIFICATION forming part of Letters Patent No. 503,987, dated August 29, 1893.

Application filed October 6, 1892. Serial No. 448,044. (No specimens.)

To all whom it may concern.-

Be it known that I, GUSTAV RUEMELIN, of Milwaukee, in the county of Milwaukee and I State of Wisconsin, have invented a new and useful Improvement in Processes of Tanning, of which the following is a description.

My invention has relation to improvements in the process of tanning.

The object of my invention is to thoroughly tan the hide without rendering it hard, and thus produce a leather having the qualities of softness and pliability to the maximum; and to this end the invention consists in the improved process hereinafter more fully set forth.

To carry my invention into effect, I take a skin of hide, previously cleaned of all impurities, such as blood, salt, lime, all mineral or organic acids, &c., and spread over the same a coating of powdered or pulverized crystal Glaubers salt, applied in a dry state. For a ten pound skin, as brought from a slaughter house in its green and wet condition, one and one-half pounds will be found a sufficient quantity for this purpose while at least six pounds should be used forhide weighing from forty to sixty pounds. About one-half of the salt is spread over the hide in the first instance, after which said hide is permitted to stand for about twelve hours in order to have the salt effectually absorb all the moisture, and when this time has expired the balance of the Glaubers salt is applied. The skins are then again exposed for a predetermined length of time, twelve hours, approximately, for light skins and twenty-four hours for The next step is to smooth the hide out upon a table and then treat the same to a composition composed of, preferably, onefourth aqua ammonia to three-fourths of oil or grease preferably unadulterated codfish oil. This is coated upon both sides of the hide by means of a brush. In the case of oils and grease of a poor quality the quantity of aqua ammonia should be less than above stated. In the case of richer oils and grease the quantity should be increased. The hide is now exposed for drying purposes, and allowed to remain in suspended position until thorough exsicoation takes place, at least two days being required for this purpose. After the drying process is completed the hide is placed in clean water to dissolve any sulphate of ammonia or any of the constituent parts of the Glaubers salt that may remain. The skin or hide is then ready for the work generally known to tanners as setting and stuffing, and after such skin or hide is dry, there is no so called staking process necessary, as the skin will remain soft. The in soluble fatty compound will remain in the skin and adhere to the fibers severally, closely, and not in a mass, leaving the fibers independent from each other, thus securing a perfect tanning and puttingthe skin in condition to reject water to a great extent.

Instead of pulverizing the crystals of Glaubers salt and applying the same in a powdered condition, theskins or hides may be placed into a solution of common salt and sulphuric acid, commonly styled, the pickle. After the skins or hides are through this pickling process the mixture of aqua ammonia and codfish oil or grease is applied in the manner previously pointed.

What I claim as new, and desire to secure by Letters Patent, is-

1. lhe process of tanning leather, which consists in coating a previously cleaned hide with Glaubers salt, and then treating the hide, after exposure, to a solution composed of aqua ammonia and grease or oil, substantially as set forth.

2. The process of tanning leather, which consists, first, in coating a previously cleaned hide with Glaubers salt, second, permitting the hide to stand for a certain time for the absorption of all moisture, third, applying a second coating of Glaubers salt, fourth, exposing the hide fora sufficient length of time, and fifth, treating the same to a solution composed of aqua ammonia and grease or oil, sub- .stantially as set forth.

In testimony whereof I affix my signature in presence of two witnesses.

GUSTAV RUEMELIN.

Witnesses:

ARTHUR L. MORSELL, O. T. BENEDICT. 

